Caption: Painful stimuli or tissue damage cause specialized neurons called nociceptors to send pain signals to the spinal cord. Pain signals enter the dorsal horn of the spinal cord where they are increased or decreased by the interneuron before continuing on to the brain. Thoughts, feelings, beliefs, etc. change the individuals experience of PAIN . Certain parts of the brain generate signals that travel back down the spinal cord to reduce or increase the strength of the signals at the interneuron. Mast cells may secrete factors which aid blood, plasma and cells in reaching the injured area. Recent research indicates that women may feel pain more acutely than men.